598 



S0DENTIA 



and anal region ; median dorsal region faintly clouded by a 

 sprinkling of black-tipped hairs ; side of muzzle, side of face 

 around and below eye, and a similar area around and below ear 

 tinged with tawny or dull ochraceous in rather noticeable 

 contrast with crown and back ; ear tawny edged with white, a 

 conspicuous clear buff tuft just below and behind meatus ; 

 underparts (except chin and anal region), inner surface of hind 

 leg and entire fore leg black, somewhat dulled by the slaty 

 under colour which appears at surface when hairs are worn or 

 disarranged ; between the black and • brown areas lie the 

 following markings in clear, light buff: (1) an area including 

 front of muzzle, upper lip and chin and extending backward to 

 level of ear in front of which it rises as a narrow band nearly 

 separating anterior and posterior tawny areas, (2) a large 

 roundish area on side of neck just in front of fore leg, (3) a 

 similar area extending backward from axilla and separated from 

 that on neck by a dusky upward prolongation of black of leg, 

 and (4) a small spot (about equal to that at base of ear) at front 

 of thigh, this last sometimes obsolete or absent; feet buffy 

 white ; tail dull yellowish brown, sometimes whitening at tip. 



Skull. — The skull is robust and heavy, about the size of that 

 of a large house rat. Dorsal profile nearly flat, but sloping 

 gradually and inconspicuously forward from lachrymal region 

 and abruptly though not very conspicuously convex over anterior 

 third of nasals; ventral profile essentially straight from behind 

 incisors to lower surface of auditory bulla, nowhere parallel with 

 dorsal profile, but nowhere conspicuously contrasted with it. 

 Brain-case roundish or somewhat diamond-shaped in general 

 outline when viewed from above (when of latter form with 

 ends truncate at lambdal and interorbital regions) ; most 

 of the surface of brain-case is formed by the broad temporal 

 areas of muscle attachment, between which lies the narrow flat 

 median region continued backward from interorbital trough, 

 narrower anteriorly than posteriorly, and bounded posteriorly by 

 that portion of lambdoid crest which lies along posterior border 

 of small, triangular or crescentic interparietal. No true sagittal 

 crest, though flat median area of brain-case becomes narrow 

 and crest-like in old individuals. Lambdal crest well developed, 

 with strong median concavity and a lateral convexity at each 

 side. Occipital region so obliquely truncate that the condyles 

 and entire upper surface of supraoccipital, from foramen magnum 

 to lambdal region, are visible when skull is viewed from above. 

 Occiput broadly arched when viewed from behind, a little 

 flattened above and at the sides, its height slightly more than 

 half mastoid width ; mastoid processes thick and short, their 

 lower border slightly above level of lower lip of foramen 

 magnum ; paroccipital processes short but well developed, 

 extending a little below lip of foramen magnum. Base of 

 brain-case with no special features, the basioccipital sloping 



